In recent years, touch input type electronic devices allowing a user to touch a surface of a screen for inputting information have been developed and produced in various forms. As a representative example of the touch input type electronic devices, a touch screen is a device that allows a user to touch a finger or a pen on a screen on which image information is displayed without using an input device such as a key board or a mouse.
Such electronic devices provide various interfaces to provide a user with a feedback. Among them, tactile feedback has widely been used.
The tactile feedback is a touch sensation felt by a finger tip of a man or a stylus pen when touching an object, and a sensation felt by a skin of body when reaching an object surface.
A device capable of playing dynamic characteristics (vibration, touch sense, operation sound, etc., transferred to a finger when a user pushes a button) as a response to when a man touches an actual object (actual button) by touching a virtual object (e.g., button display of a window screen) among devices using tactile feedback is the most ideal. To improve the performance of the tactile feedback device, a conventional mechatronic device or the like using a motor and a link mechanism has been used up to now.
However, a conventional mechatronic device has disadvantages that volume and energy consumption are large, and a small fault frequently occurs because of many components. Because a response speed of the conventional mechatronic device is low, tactile feedback may not be instantly provided. Due to this, the user can not be provided with a sufficiently actual feeling or has inconvenience of use.